Counter Synergy

Duskshell Crawler

When this creature enters, put a +1/+1 counter on target creature.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Duel for Dominance

Coven — Choose target creature you control and target creature you don't control. If you control three or more creatures with different powers, put a +1/+1 counter on the chosen creature you control. Then the chosen creatures fight each other. (Each deals damage equal to its power to the other.)

Pridemalkin

When this creature enters, put a +1/+1 counter on target creature you control.
Each creature you control with a +1/+1 counter on it has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Timberland Ancient

Reach, trample
Forestcycling {2} ({2}, Discard this card: Search your library for a Forest card, reveal it, put it into your hand, then shuffle.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Forest

Break Ties

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.
Reinforce 1—{W} ({W}, Discard this card: Put a +1/+1 counter on target creature.)

Beastrider Vanguard

{4}{G}: Look at the top three cards of your library. You may reveal a permanent card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Plains

Sunder the Gateway

Choose one —
• Destroy target nontoken artifact or enchantment an opponent controls. Incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)
• Incubate 2, then transform an Incubator token you control.

Mandibular Kite

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 and has flying.
Equip {3}{W}

Command Tower

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
This creature attacks each combat if able.

Soltari Visionary

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever this creature deals damage to a player, destroy target enchantment that player controls.

Khalni Garden

This land enters tapped.
When this land enters, create a 0/1 green Plant creature token.
{T}: Add {G}.

Brightfield Glider

Vigilance
Whenever this creature attacks while saddled, it gets +1/+2 and gains flying until end of turn.
Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Turntimber Grove

This land enters tapped.
When this land enters, target creature gets +1/+1 until end of turn.
{T}: Add {G}.

Serpent-Blade Assailant

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Deathtouch

Gingerbread Cabin

({T}: Add {G}.)
This land enters tapped unless you control three or more other Forests.
When this land enters untapped, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Wings of the Guard

Flying
Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)

Light of Hope

Choose one —
• You gain 4 life.
• Destroy target enchantment.
• Put a +1/+1 counter on target creature.

Blighted Burgeoning

Enchant land
When this Aura enters, incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Deepwood Denizen

Vigilance (Attacking doesn't cause this creature to tap.)
{5}{G}, {T}: Draw a card. This ability costs {1} less to activate for each +1/+1 counter on creatures you control.

Pollenbright Druid

When this creature enters, choose one —
• Put a +1/+1 counter on target creature.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Gift of the Viper

Put a +1/+1 counter, a reach counter, and a deathtouch counter on target creature. Untap it.

Skyhunter Skirmisher

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Over the Edge

Choose one —
• Destroy target artifact or enchantment.
• Target creature you control explores, then it explores again. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard. Then repeat this process.)

Soltari Trooper

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever this creature attacks, it gets +1/+1 until end of turn.

Fleeting Flight

Put a +1/+1 counter on target creature. It gains flying until end of turn. Prevent all combat damage that would be dealt to it this turn.

Healer's Hawk

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Kutzil, Malamet Exemplar

Your opponents can't cast spells during your turn.
Whenever one or more creatures you control each with power greater than its base power deals combat damage to a player, draw a card.

Take Up the Shield

Put a +1/+1 counter on target creature. It gains lifelink and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Basking Broodscale

Devoid (This card has no color.)
{1}{G}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on this creature, you may create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this token: Add {C}."

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Hidden Courtyard

This land enters tapped.
{T}: Add {W}.
{4}{W}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Lull

Prevent all combat damage that would be dealt this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Dusyut Earthcarver

Reach
When this creature enters, it endures 3. (Put three +1/+1 counters on it or create a 3/3 white Spirit creature token.)

Scrounging Bandar

This creature enters with two +1/+1 counters on it.
At the beginning of your upkeep, you may move any number of +1/+1 counters from this creature onto another target creature.

Greatsword of Tyr

Whenever equipped creature attacks, put a +1/+1 counter on it and tap up to one target creature defending player controls.
Equip {W} ({W}: Attach to target creature you control. Equip only as a sorcery.)

Longstalk Brawl

Gift a tapped Fish (You may promise an opponent a gift as you cast this spell. If you do, they create a tapped 1/1 blue Fish creature token before its other effects.)
Choose target creature you control and target creature you don't control. Put a +1/+1 counter on the creature you control if the gift was promised. Then those creatures fight each other.

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

Holy Cow

Flash
Flying
When this creature enters, you gain 2 life and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

New Horizons

Enchant land
When this Aura enters, put a +1/+1 counter on target creature you control.
Enchanted land has "{T}: Add two mana of any one color."

Mirran Bardiche

For Mirrodin! (When this Equipment enters, create a 2/2 red Rebel creature token, then attach this to it.)
Equipped creature gets +2/+1 and has vigilance.
Equip {3}{W} ({3}{W}: Attach to target creature you control. Equip only as a sorcery.)

Elven Rite

Distribute two +1/+1 counters among one or two target creatures.

Goldvein Pick

Equipped creature gets +1/+1.
Whenever equipped creature deals combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Captured by Lagacs

Enchant creature
Enchanted creature can't attack or block.
When this Aura enters, support 2. (Put a +1/+1 counter on each of up to two target creatures.)

Tuskguard Captain

Outlast {G} ({G}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has trample.

Gingerbrute

Haste (This creature can attack and {T} as soon as it comes under your control.)
{1}: This creature can't be blocked this turn except by creatures with haste.
{2}, {T}, Sacrifice this creature: You gain 3 life.

Poison Dart Frog

Reach
{T}: Add one mana of any color.
{2}: This creature gains deathtouch until end of turn.

Prevent all combat damage that would be dealt this turn.

Armadillo Cloak

Enchant creature
Enchanted creature gets +2/+2 and has trample.
Whenever enchanted creature deals damage, you gain that much life.

Shinewend

Flying
This creature enters with a +1/+1 counter on it.
{1}{W}, Remove a +1/+1 counter from this creature: Destroy target enchantment.

Evolution Witness

{1}{G}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)
Whenever one or more +1/+1 counters are put on this creature, return target permanent card from your graveyard to your hand.

Nightshade Dryad

Deathtouch
{T}: Add {C}.
{T}: Add one mana of any color.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Ankle Biter

Elvish Visionary

Nyxborn Hydra

Bestow {X}{G}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Reach, trample
This permanent enters with X +1/+1 counters on it.
Enchanted creature gets +1/+1 for each +1/+1 counter on this Aura and has reach and trample.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Miner's Guidewing

Flying, vigilance
When this creature dies, target creature you control explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.)

Converter Beast

When this creature enters, incubate 5. (Create an Incubator token with five +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)

Topiary Panther

Trample
Basic landcycling {1}{G} ({1}{G}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Travel Preparations

Put a +1/+1 counter on each of up to two target creatures.
Flashback {1}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ainok Bond-Kin

Outlast {1}{W} ({1}{W}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has first strike.

Creosote Heath

This land enters tapped.
When this land enters, it deals 1 damage to target opponent.
{T}: Add {G} or {W}.

Paladin's Arms

Job select (When this Equipment enters, create a 1/1 colorless Hero creature token, then attach this to it.)
Equipped creature gets +2/+1, has ward {1}, and is a Knight in addition to its other types.
Lightbringer and Hero's Shield — Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Colossal Dreadmask

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +6/+6 and has trample.
Equip {3}{G}{G}